Amir Khan has pledged to return "better, more skilled and smarter" when he ends what will be a 13-month absence from the ring on Floyd Mayweather's undercard on May 3.

Khan has not fought since a poor points win over Julio Diaz in Sheffield last April but will be back in action when he makes his welterweight debut against American Luis Collazo in Las Vegas.

That fight takes place on the undercard for Mayweather's bout against Marcos Maidana at the MGM Arena - a showdown against the pound-for-pound superstar Khan had, until recently, been hoping was going to be his.

The 27-year-old Bolton boxer must now continue his wait for a chance to face Mayweather, but in the meantime he is eagerly looking forward to getting back into action against notoriously awkward southpaw Collazo.

He told Press Association Sport: "Collazo is a very dangerous fighter and he's beaten (former world champion Victor) Ortiz so it proves that I want to move up in weight and take on the big fights from the start

"But being out of the ring for so long has helped me work on a lot of different things that you usually wouldn't get the time to focus on when you're in a training camp for a fight.

"It has come at the right time for my move up in weight, and it is going to make a massive difference. You'll see a different fighter - better, more skilled, patient and smarter. I can't wait to get back in there and cause some hurt."

The Olympic silver medallist has admitted making mistakes in his relentless pursuit of Mayweather, including passing up a shot at the then IBF champion Devon Alexander late last year, before Mayweather last month chose instead to face Maidana.

Khan remains confident he will one day get his opportunity at WBC welterweight world champion Mayweather, though, adding: "I do regret a few things and I should have taken the Alexander fight because I'd have been a world champion now.

"Obviously that didn't happen then the Mayweather fight fell through. I should have got one more fight in and it's a mistake that I will never make again.

"Mayweather decided not to take the fight with me, probably because he thought I would be the first to take away his unbeaten record, and is now fighting somebody I've already beaten.